Tig welding aluminum, how to maintain heat control?

admin

Hello all , it has been a while since I have posted any pics of my work, but am on often learning/reading from other posts. What im really looking for is any feedback in helping me with heat control and torch angle. This seems to be my biggest problem when it comes to consistency/laying clean beads. When the base metal heats, do I just need to move faster & maintain heat control w/my pedal by backing down but still paying attention to the puddle size? I think im seeing whats going on but want to hear from the pros on what they are seeing . butt joints in horizontal postion seem to go together much better for me when dealing w/the heat control issue. This was my 1st box I've done & I definetly need help on wrapping the corner w/o blowing it in . also I see the little specs of black in the weld (contamination) which I believe comes from my torch angle or dirty parts of the base metal?  I like working w/the aluminum b/c I think I see whats going on a bit better than the steel/stainless I've worked on. All advice would be appreciated. 1/8 plate, 1/16 tung, filler 3/32, amps 90-110 w/foot control. Attached ImagesMillermatic 211 auto-set w/spool gun Diversion 165375 XtremeDigital elite
Reply:do I just need to move faster & maintain heat control w/my pedal by backing down but still paying attention to the puddle size? Short answer YES to all. The material will only accept so much energy then mean old Mr. Gravity takes over. angle of the torch (direction of the arc) will have minimal affect. Better is to feel how fluid the puddle is, see how wet is it, see how wide it is and adjust the heat input. I start at open ends working to closed ends. Open ends need less energy input to get the puddle started.
Reply:The best way that I have found to work on torch angle heat settings filler dabbing technique travel speed and so on was to cut yourself a piece of 10x10x1/8 piece of aluminum and start laying beads across it from one end to the other and stack them side by side. That will help a lot and it's not that expensive to practice as your eliminating using good material to pracie on and you can run many many beads on it. Find a technique that works well for you by doing this and practice it. Try doing different things such as cranking up your heat and learning how to control the heat once the work piece starts to get hot. In some of the pics it looked as if you were getting to hot and adding to much filler then trying to compensate by lowering the heat and causing it to cold lap. Try practicing like I said and then start on fillet welds. I know just running beads is a different ball game than working on fillets but once you have control and can make your beads uniformed the way you want them then apply what you learned to a fillet and it will be much easier for you.1973 Lincoln SA 200, Already replaced shunt coils, Idle board (SOLD)1984 Miller Dialarc 250HF, Miller water cooler, 250 AMP water cooled torch, you know the worx.
Reply:this video shows how the foot pedal is used on aluminum. You will have some people tell you that it is wrong but they are full of it. It's a different way of welding than wide open throttle all the time with little movement of the pedal. You might want to try it and if it works for you then great, if not then keep practicing. I would say this is manual pulsing and the end result looks great if you can get in a rhythm. I have used this technique and prefer it if you are going for a nice aesthetic look with quality weld strength. It also helps keep the heat down if you are welding thin gauge.P.S. I would probably not start an arc while the tungsten is still red hot and just take your time. this guy seems like he is a hurry.Miller Dynasty 200Millermatic 211Instagram?.... find me @ WELD_MEDIC
Reply:Originally Posted by tig_21this video shows how the foot pedal is used on aluminum. You will have some people tell you that it is wrong but they are full of it. It's a different way of welding than wide open throttle all the time with little movement of the pedal. You might want to try it and if it works for you then great, if not then keep practicing. I would say this is manual pulsing and the end result looks great if you can get in a rhythm. I have used this technique and prefer it if you are going for a nice aesthetic look with quality weld strength. It also helps keep the heat down if you are welding thin gauge.P.S. I would probably not start an arc while the tungsten is still red hot and just take your time. this guy seems like he is a hurry.
Reply:For those who don't have a pulser on their tig machine it's great. It's something to try to get into a rhythm and it might help with consistency.Miller Dynasty 200Millermatic 211Instagram?.... find me @ WELD_MEDIC
Reply:tig_21,Obviously, you know nothing about tig welding aluminum (along with the guy in the video).There are VERY FEW situations where pulsing is advantagous on aluminum, whether you're doing it with the pedal or setting the machine up for pulse.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:To the OP from a newbie! .125" thick alum should usually have near 125 amps. 1 amp per .001 thickness is a guideline I've heard here, there, and elsewhere.A lot of times on aluminum I've found that the need is not only to go faster, but also to go hotter while you do it. Give it a shot.Aluminum likes a whole lot more speed than steel. Heat it up to get started and get your butt moving like you stole something lol.  Take your time setting up the initial puddle and then hammer down on the speed. With text it's tough but something like.... Light up and swirl to make a puddle, wait for the puddle, wait, wait, oh there is that puddle, now dip 'n move, wait a fraction, dip 'n move, wait a smaller fraction, dip 'n move, wait a smaller fraction, dip 'n move, dip 'n move, dip 'n move, start backing off the pedal and dip 'n move, back off a little more and dip 'n move, back off a little bit more and dip 'n move, etc etcOf course this all depends on thickness, joint style, fit up, overall mass of the weldment, length from edge to edge, and others but you get the idea. You can't just light up on alum and use a fixed timing and/or a fixed amperage or you'll probably be to cold (or too slow to compensate) at the beginning and too hot or too fast at the end.Take this with a grain of salt as I am still learning too but steel is so much more forgiving than alum. One nice thing I've found is that after doing some AC  on alum (no matter how bad or good) and then switching to steel, the steel is SO much slower and easier.How do you know the blacksmith's dog? When you hollar at him he makes a bolt for the door!
Reply:Originally Posted by bitchiNweldsWhen the base metal heats, do I just need to move faster & maintain heat control w/my pedal by backing down but still paying attention to the puddle size? I think im seeing whats going on but want to hear from the pros on what they are seeing . butt joints in horizontal postion seem to go together much better for me when dealing w/the heat control issue.  I like working w/the aluminum b/c I think I see whats going on a bit better than the steel/stainless I've worked on. All advice would be appreciated. 1/8 plate, 1/16 tung, filler 3/32, amps 90-110 w/foot control.
Reply:Recently, I've started pulsing with my foot, and it's kind of grown on me, because you can do some things that aren't possible with a constant current.  I find I can use it to shape the profile of the droplet that is deposited as the weld bead.  For example, I can make a "dime" droplet shape (flat cylindrically shaped droplets) by an initially high blast of current and then some filler rod add, then perhaps a bit more current without filler being added (to flatten the top of the droplet), then move.Or I can make hemisperically shaped droplets, if I taper off the current as the filler rod is added, the base of the droplet freezes progressively to the top, so it "mounds up" the droplet (and you can control to what extent you want it mounted up depending on how much filler you add as this is done, too.)The other thing I like about it is, I feel more free to speed up or slow down as needed (say, to change pace for letting the filler rod hand keep up, or to increase pace if you just want to go faster.)I certainly wouldn't say it is "the [only] way" to weld aluminum, or even the best way.  One downside when you're shaping every droplet with the footpedal, is that is adds extra variables to try and hold consistent, which can get screwed up if you do it wrong.  Generally, it's better to have less that can go wrong.I'm not sure if I even recommend that people do it.  I think it's pretty hard to get the knack of (to use for droplet profile shaping, at least) and you better master the more steady current technique first.  (You can still vary the droplet profile with how much heat you are using and the arc characteristics)I am not a fan of using machine pulsing with aluminum either.  High frequency pulsing can be used to stiffen an AC or DC arc, but if that is necessary to accomplish on an AC arc, a better way to do it seems to be to alter the AC frequency. Attached Images
Reply:For me as a newbie ^those^ beads look too far apart. It's that or he has incredible patience. I can't slow down enuf on alum myself to move that far and dip that slowly to get those kinda beads. But again I'm still learning. I do envy the consistency though.^^^ pretty much what EDIT: he (DSW) said too! ^^^He is smarter than me. I hope these explanations help somewhat.From me you just get the dumbed down version LMAO Edit: everybody is posting at the same time lolLast edited by that'll_buff_out; 04-18-2012 at 10:38 PM.How do you know the blacksmith's dog? When you hollar at him he makes a bolt for the door!
Reply:Originally Posted by that'll_buff_outA lot of times on aluminum I've found that the need is not only to go faster, but also to go hotter while you do it. Give it a shot.Aluminum likes a whole lot more speed than steel. Heat it up to get started and get your butt moving like you stole something lol.  You can't just light up on alum and use a fixed timing and/or a fixed amperage or you'll probably be to cold (or too slow to compensate) at the beginning and too hot or too fast at the end.  steel is so much more forgiving than alum. One nice thing I've found is that after doing some AC  on alum (no matter how bad or good) and then switching to steel, the steel is SO much slower and easier.
Reply:Thanks Doug, That helps me too!How do you know the blacksmith's dog? When you hollar at him he makes a bolt for the door!
Reply:Just keep practicing and it'll come to you. The foot stomping stuff is bogus for anything critical enough to merit a WPS described by a Welding Engineer. Those ornamental welds look appealing to the eye of a novice but the inconsistent reinforcement would fail to meet any requirement for structural or pressure that I've ever welded.Tap the other toe if you feel like it but the one on the pedal should be smooth and purposeful while the blue light is on.Two turn tables and a microphone.
Reply:^I agree with everything except that the light is not always BLUE lol ^                                                                                   How do you know the blacksmith's dog? When you hollar at him he makes a bolt for the door!
Reply:Dip and move 1/8in at 1 second intervals and watch the width of your weld.  You want to see 8-10 ripples per in.  Clean 1/2in from the weld zone because it will suck in contaminants.
Reply:Another newbie here.  Just keep doing it and it will come to you.  All the good advice above will help, but you have to keep going and eventually you will just get a feel for it.  I usually try to get the metal to keyhole a bit before adding filler, that way I know I'm fully penetrated with the weld.I find outside corners particularly hard to get a nice looking bead on.  You can do different types of fitups with those outside corners that may help the appearance too.  Laying a nice looking bead on a flat plate and making nice beads in different positions on different types of joints are two different animals.  No disrespect meant, but Jackeru's welds look like they are probably penetrated in a few spots, but not fully throughout the weld length.  When you let the weld area keyhole, you know you're through the metal all the way.  I try this with every weld and even if the bead doesn't look perfect, I know it's gonna be strong.  The appearance of a nice stack of dimes should automatically happen when the weld is being done well, not the other way around.TA Arcmaster 300CM3XMT 304S22P12 suitcase feederX-Treme 12VSOptima pulserTA161SMaxstar 150STLHypertherm PM45OP setupStihl 020AVP, 039, 066 Magnum
Reply:thanks all on the feed back, will continue to apply this to my practice, practice, practice. will also focus more on turning my amps up when welding aluminum b/c I do bel DSW hit the nail on the head about over heating the work piece & then creating the puddle. will look & research more on key hole, fillet welding.Millermatic 211 auto-set w/spool gun Diversion 165375 XtremeDigital elite
Reply:You might want to look at these two posts by Kevin Morin here.http://weldingweb.com/showpost.php?p...6&postcount=40http://weldingweb.com/showpost.php?p...2&postcount=17.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by Drf255No disrespect meant, but Jackeru's welds look like they are probably penetrated in a few spots, but not fully throughout the weld length.  When you let the weld area keyhole, you know you're through the metal all the way.  I try this with every weld and even if the bead doesn't look perfect, I know it's gonna be strong.  The appearance of a nice stack of dimes should automatically happen when the weld is being done well, not the other way around.